---
title: "Monitor"
description: "an armed condition that makes matches"
section: concepts
address: /concepts/monitor
contract: 0476e35e6e275db5
---

# Monitor

an armed condition that makes matches

[figure: Monitor is a definition at follows scope. The drawing shows its fields and the objects that they point at.]

| property | value |
|---|---|
| kind | definition |
| scope | follows |
| key | its own id, versioned |
| store | postgres |
| family | rules_engine |



## Fields


| field | type | required | note |
|---|---|---|---|
| `name` | `text` | yes |  |
| `predicate` | `hash` | yes | by its hash |
| `place` | [PlaceARunsAt](/concepts/placearunsat) | yes |  |
| `strategy` | `id` | yes | the brand's standing strategy unless one is chosen |
| `kind_of_signal` | [KindOfSignal](/concepts/kindofsignal) | yes |  |
| `armed` | `bool` | yes |  |
| `armed_with` | `id` | no | the preview its armed version was judged by |
| `last_answer` | [MonitorAnswer](/concepts/monitoranswer) | no | kept on every beat |
| `vertical` | `id` | no | for a platform monitor: the vertical it keeps full |



## Routes that use it
- [`/v1/act/arm_monitor`](/reference/act/arm_monitor) returns it
- [`/v1/act/keep_monitor`](/reference/act/keep_monitor) returns it